It may be that the idle and cap jets have been switched. I've seen this before, and yet the engine still ran. The shorter of the two is the cap jet, while the longer one is the idle jet. They both have the same thread size, so they can easily be switched. When the main and cap jets are in place, there should be a very slight height difference between them to compensate for the angle that the engine sits. When the carb is mounted to the manifold flange, the jets are more or less about at equal heights. Make sure both of them have a concave (dipped inwardly) tip so that gasoline doesn't drip out of them. Many repo jets are simply cut flush across the tops, so weeping gas is a problem. The idle jet doesn't take a gasket, by the way.
Marshall
